Sonata, BIM and pre-Revit software

If you were to ask around who invented Revit, the answer would almost always be the same: Autodesk. The year 2000, or thereabouts. The software that changed the way buildings are designed, born in some Californian laboratory along with the rest of the Autodesk catalog. It’s a convenient answer, but it’s wrong.

Revit didn't start from scratch, nor did it originate from Autodesk — which bought it in 2002, when the product had already existed for years. It was born from a technical legacy that began much earlier, in an era when 3D was considered science fiction and the rest of the industry was still enchanted by the 2D of AutoCAD, which had been released just three years prior.

There is a piece of software, from 1986, that was already doing things we consider obvious today: walls that "know" how to host doors and windows, views that update themselves, a model that behaves — not by chance — in a surprisingly familiar way. It was called Sonata. And before it led to Revit, its history passed through an attic, a bank loan, and a deal that fell through due to a stock market crash that no one could have foreseen.

Sonata is born in an attic

In 1986, Jonathan Ingram was 24 years old. He was already working in the industry — at GMW Computers, he had contributed to Rucaps, one of the first serious attempts to move the 2D logic of plans and sections toward something more like a model. But for Ingram, that wasn't enough. While others were content with adding 3D views to a system designed for 2D, he saw something else: a single, parametric model where every object understands its own relationships with the others — walls that recognize openings, views that keep themselves synchronized, clash detection, integrated rendering.

It was too big an idea to remain within the company where he worked. So he left. He didn't open a studio, didn't find a partner, didn't seek venture capital. He asked for a bank loan, bought a workstation, and shut himself in an attic. Literally — that is where he worked, alone, for two years.

It’s the scene that in a movie would be the transformation montage: the protagonist isolated, obsessed with an idea that no one around him is seeing yet, while the rest of the world moves on, convinced that 2D is more than enough. The genius in the garage — only here, the garage is an attic in London, and the idea isn't a computer, but the first true ancestor of BIM.

By 1986, the work was finished. The software was called Sonata. It hit the market a year before ArchiCAD, fifteen years before Revit — and it made a splash. It won awards. For the work he did on Sonata (and on what would follow), Ingram would years later receive the Prince Philip Gold Medal, one of the highest British engineering honors. But the real question isn't what he built. It is how — because what is inside Sonata is where the story that leads us to Revit truly begins.

Sonata vs Revit: the technical comparison

Looking at Sonata's specifications today, the feeling is strange. It doesn't seem like a distant ancestor — it feels like a prototype.

The heart of the system was parametric, object-oriented solid modeling: objects weren't just raw geometry, but categories that knew how to relate to one another. A door inserted into a wall didn't stay there by chance — the wall "knew" how to host it, and it automatically generated the associated details. Sound familiar? It’s the same host/insert principle upon which we still build our families today.

And it doesn't end there. Plans, sections, and 3D views updated together, automatically, with every modification — the same promise we call "model coordination" today. Sonata generated quantity take-offs, managed the construction sequence, and even had an integrated rendering engine (Ingram wrote his doctoral thesis on it). All this on a Unix workstation, in 1986.

So what is missing? What really separates Sonata from Revit, if the underlying concept is the same? The answer is access.

Sonata was powerful, but to build and modify that parametric logic, you needed a dedicated programming language. Staff were specially trained to use it — this isn't a marginal detail; it’s the difference between a tool for specialists and a tool for an entire profession. Sonata had the engine. It didn't have the cockpit.

Revit arrived fifteen years later with exactly that missing piece: the Family Editor. Not a language to learn, but a graphical interface — the exact same parametric logic as Sonata, made manipulatable by anyone who knows how to draw, without writing a line of code. That is where BIM ceases to be a laboratory experiment and becomes a workflow scalable across an entire studio, an entire industry.

In other words: Sonata proved that the idea worked. Revit proved that the idea could work for everyone.

The missed opportunity

In 1987, one year after its launch, Sonata was doing exactly what it was supposed to: convincing the market that the future belonged to it. And among those who took notice was Autodesk.

According to Ingram himself, they came very close to an acquisition agreement. Negotiations were advanced, the terms basically defined. Then, within a few days, everything fell through — not because of a disagreement, not because of a contractual detail, but because the whole world was distracted by something much bigger: Black Monday, the stock market crash of October 19, 1987, one of the darkest days in Wall Street history. The deal, quite simply, never happened.

There is no obvious moral to be drawn from this — it wasn't an error by Ingram, nor was it an opportunity wasted through negligence. It is the type of episode that happens more often in the history of technology than you might think: perfect timing ruined by an event that has nothing to do with the product itself.

But the reason it is worth telling isn't because of the bad luck itself. It is what happens next, fifteen years later: Autodesk, the same company that was about to buy Sonata in '87, would buy Revit in 2002 — the indirect heir to that same technical logic, which had reached maturity through a completely different path.

Sometimes companies don't chase the right ideas. They encounter them twice, a generation apart, until they arrive at the moment when the market is finally ready to welcome them.

From Sonata to Reflex to PTC

Having lost the opportunity with Autodesk, Ingram didn't stop. He returned to the attic — metaphorically, as the project had since grown — and continued to develop what he had built. Sonata evolved, was refined, and became a more complete and mature application: Reflex.

Reflex brought the same logic of Sonata to new hardware, Silicon Graphics IRIX workstations, and then to PC desktops with the Pro Reflex version — a step toward a wider audience, even if still far from the scale that Revit would reach.

In 1996, the turning point came that no one, ten years earlier, would have predicted: Reflex was sold to PTC — Parametric Technology Corporation — for a sum that, according to sources at the time, was around 30 million dollars. Ingram himself joined PTC as CTO.

PTC, it must be said, is no ordinary company in the world of parametric modeling. It is the giant of mechanical CAD, famous above all for Pro/Engineer — the application that had already redefined parametric design in the industrial sector. The acquisition of Reflex had a precise goal: to use that technology to enter the construction market, a sector PTC saw as the next growth frontier.

On paper, the deal had everything going for it. PTC had the money, the consolidated technology of Pro/Engineer, and now also Reflex and its creator. Yet the strategy never took off — the construction market proved more difficult to penetrate than expected, and the initiative was progressively downsized. But within PTC, in those years, there were also two other people who were looking at that exact same technology with different eyes — and who, shortly thereafter, would make a choice that would change everything.

The human bridge

Leonid Raiz and Irwin Jungreis worked at PTC as key developers on Pro/Engineer — the same Mecca of mechanical parametric CAD software that made PTC a giant. They were there when Reflex arrived, and they stayed long enough to understand something that almost no one else in the company seemed to see with the same clarity: PTC held the right technology, but they were trying to sell it to the wrong market, with the wrong approach.

In 1997, they made a clean break. They left PTC — and in their severance, they took with them something very concrete: a non-exclusive license for the Reflex source code. They didn't start from zero. They started from fifteen years of work that passed from Sonata to Reflex, inherited legally and technically.

On October 31, 1997, they founded Charles River Software, in Newton, Massachusetts. The declared goal was clear from the beginning: to bring the power of parametric modeling — already proven in mechanical engineering by Pro/Engineer, and in construction by Reflex — to an audience that neither of the two predecessors had truly managed to reach: the entire architectural profession, not just the specialists willing to learn a programming language.

There is a detail that closes the circle in an almost poetic way: according to Ingram himself, Raiz and Jungreis offered him a role in the new project. He refused. After more than a decade between Sonata and Reflex, he felt exhausted — another adventure of the same kind was simply too much.

Charles River Software, three years later, would change its name. It would be called Revit Technology Corporation.

If all this is true — if Sonata was already doing things in 1986 that we take for granted today — why has almost no one ever heard of it? Why is it that in BIM courses, in webinars, in industry conferences, the story always starts from Revit or, at most, from Eastman, and Sonata remains a name for insiders?

The answer is not a conspiracy or a damnatio memoriae. It’s simpler, and more predictable.

The first reason is the cost. Sonata ran on Unix workstations and Silicon Graphics — hardware that cost as much as an apartment, accessible only to studios with significant budgets. AutoCAD, released a few years earlier, ran on the first IBM PC. Cheap, widespread, within reach of anyone. It isn't hard to understand which of the two won the battle for mass adoption.

The second reason is the workflow. The construction industry, unlike the mechanical one, has a historically slow rate of technological adoption — architects, contractors, and clients proceed at different speeds, and the transition from 2D to 3D imposed a radical change in habits that the market of the 80s simply wasn't ready to digest. Sonata asked the industry to take a leap that the industry itself wasn't yet capable of taking.

The third reason is the timeline. Sonata and Reflex arrived before there were standards, guidelines, and a BIM culture shared at an industry level. They were born without common ground to take root in — a bit like launching a perfect product in a market that doesn't exist yet.

The result is that Sonata and Reflex still built an international user base — UK, China — but remained out of the spotlight of official history, while attention shifted entirely to the rivals that arrived later, with better market and timing luck.

It was never a question of technical quality. It was always a question of when.

The BIM Culture rule

There is an easy temptation, at this point: to think that Sonata was "a missed opportunity." It wasn't. Sonata did exactly what it was supposed to do — it proved that the idea worked, technically, fifteen years before the market was ready to accept it on a large scale. It isn't a failure. It is a prototype that waited for the right moment to become standard, passing from hand to hand — from Ingram to Reflex, from Reflex to PTC, from PTC to two developers who saw what no one else, at that moment, was seeing.

The BIM Culture rule — a sound technical idea isn't enough. It must meet a market, hardware, and professional culture ready to receive it — and when this encounter doesn't happen, the idea doesn't die: it waits, changes shape, passes to other hands, until someone finds the combination that makes it explode.

Sonata had the engine. What was still needed was someone to build the cockpit — and that someone, three years after leaving PTC with a license in their pocket and an inherited idea, had a very specific name.

How Raiz and Jungreis arrived there, what they had to solve, and why the Family Editor — not the rendering, not the parametric modeling itself, but that very interface — was the true invention that made Revit win where Sonata and Reflex had stopped: this is the story we tell in the next episode of BIM Culture, "The Birth of Revit".

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If you want to delve deeper into the complete genealogy of BIM, I recommend reading the BIM Culture article The Prophet of BIM — Charles M. Eastman.